European Commission, branch of the governing body of the European Union (EU) invested with executive and some legislative powers. Located in Brussels, Belgium, it was founded in 1967 when the three treaty organizations comprising what was then the European Community (EC) were officially merged; previously, each organization was governed by a separate commission. The commission is composed of 30 members—two from each of the five largest EU nations and one from each of the others. Members are appointed by agreement among the member nations and serve four-year terms. One member serves as president and six serve as vice presidents. A large administrative staff, numbering some 24,000, is divided among many committees and administrative agencies. The commission implements the provisions of the EU's founding treaties and carries out rules issued by the Council of the European Union.

In keeping with the objective of the founding treaties, the commission initiates EU policy on the economy in particular but, increasingly, also on environmental and foreign and security affairs. The legislation it drafts is subject to amendment by the European Parliament and to ratification by the Council of the European Union. It was under the presidency of Jacques Delors (1985-95) that the commission put forward the Single European Act (1987) and the Treaty of European Union (1992; also known as the Maastricht Treaty), both of which provided for a significant expansion of the EU's powers. In 1995, Jacques Santer of Belgium became president of the commission. The entire commission resigned in 1999 amid accusations of financial mismanagement, corruption, fraud, and nepotism, and a new set of commissioners, with Romano Prodi of Italy as president, was appointed later the same year. In 2004, José Manuel Barroso succeeded Prodi as president.